John Crane Mechanical Seal Type SB1 is a stationary mounted, multispring, balanced seal supplied as a standard cartridge assembly. A key feature of Type SB1 is that the springs are stationary and located outside the process fluid. They are therefore protected from clogging by dirty and fibrous products. The construction means that as faces wear the patented PTFE slot ring (which replaces the traditional O-ring preventing hang-up and O-ring ‘rolling’) moves onto a clean part of the primary ring housing, reducing the risk of hang up caused by dirty or crystallising products. The standard rotating seat is a shrunk-in silicon carbide, the standard primary ring is carbon or silicon carbide shrunk into stainless steel (a hard face option of tungsten carbide is available)

The Safeseal Type SB1 is a single-cartridge seal for use with clean fluids and lubricants. It is versatile and easy to install and maintain. Although the design of the seal is simple, it contains advanced technical features, such as patented seal face holders and elastic mating ring. Seal faces are installed using a patented heat shrink process ensuring correct, distortion-free face alignment at all recommended temperatures. The Type SB1 seal is applicable for a wide range of duties such as water, oil, solvents and pulp.